Fibrillogenesis or reconstitution of soluble tropocollagen into native collagen fibers and aggregate is well known in the art. For example, U.S. Pat. No. 3,075,961 describes one method for reconstituting collagen from acid precursor gelatin. Volume 5 of the Molecular Biology series entitled "The Macromolecular Chemistry of Gelatin" by Arthur Veis (1964) also describes in detail the production and processing of collagen.